I think it is universally true that women are uncomfortable pumping in front
of men.  Most women don't like to pump in a crowd -- of either gender.  But I
don't think the issue is so much the equipment as much as the relative
nudity.  When you breastfeed, little or nothing typically shows.  There is
much more exposure involved in pumping.  I think the general unwillingness to
be half-naked is the biggest driving force.

- Dia